MySql - SubQuery is not working properly

Question

BubQuery always return the empty result if the query is correct.

1st Query:

SELECT * FROM `user` WHERE user_age IN(1,22,34);

Result:

2nd Query:

SELECT GROUP_CONCAT(user_age_list) AS user_age FROM `user_detail` WHERE id='1';

Result:

I am try:

SELECT * FROM `user` WHERE user_age IN(SELECT GROUP_CONCAT(user_age_list) AS user_age FROM `user_detail` WHERE id='1');

Sqlfiddle: http://sqlfiddle.com./#!9/d6515f/3 //This is a sample table.

Above the query is always return the empty rows. But each of query return the result if its run single. Really I don't know where is the error. Please update the answer or suggest me.

Answer 1

Avoid Use of GROUP_CONCAT

SELECT * 
FROM `user` 
WHERE user_age IN(SELECT user_age_list FROM `user_detail` WHERE id='1');

UPDATED

SELECT * 
FROM `user` u 
WHERE EXISTS (SELECT 1 FROM `user_detail` ud  WHERE id='1' AND ud.user_age_list = u.user_age)

Answer 2

SELECT * 
FROM user
WHERE user_age IN 
(SELECT user_age_list user_age 
 FROM user_detail
 WHERE id='1');

You don't need the group concat here. The engine knows the result set is an inclusive list without the group concat.

What it is trying to do is compare the '1,22,34' to each user_age which is why you get no results.

1 <> '1,22,34'
22 <> '1,22,34'
34 <> '1,22,34' 

thus no results.